Related Party Transactions (Details Textual) $ in Millions	3 Months Ended	9 Months Ended
Sep. 29, 2018 USD ($)	Sep. 29, 2018 USD ($)
Powersem
Related Party Transaction [Line Items]
Revenue from related parties	$ 0.2	$ 0.6
Purchase from related party	1.3	3.4
Receivable from related parties	0.1	0.1
Payables to related parties	0.2	0.2
EB Tech
Related Party Transaction [Line Items]
Payables to related parties	0.1	0.1
Amount of transaction	0.1	0.3
ATEC
Related Party Transaction [Line Items]
Payables to related parties	0.6	0.6
Amount of transaction	$ 2.5	$ 7.7
Powersem
Related Party Transaction [Line Items]
Ownership percentage	45.00%	45.00%
EB Tech
Related Party Transaction [Line Items]
Ownership percentage	20.00%	20.00%
ATEC
Related Party Transaction [Line Items]
Ownership percentage	24.00%	24.00%

Amount for accounts payable to related parties.

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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Amount of transactions with related party during the financial reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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